Abstract: A current storing circuit capable of having a small area, a simple structure with the small number of devices, a low consumption current operation and high yield in manufacturing is provided. Applying the current storing circuit to the current-driving type of display device such as an OLED display device can improve the aperture rate of pixels and reliability of the display device as well as highly functionalize the display device. The invention is characterized by using a new semiconductor element in a shape of a transistor having plural drains or sources. When the semiconductor elements is used for both of a writing element and a driving element, reading in and storing a current value and outputting the current can be performed by only the two semiconductor elements, so that the area occupied by the devices would be easily reduced significantly.

Abstract: An inexpensive light emitting device and inexpensive electric equipment are provided. A substrate on which a semiconductor element or a light emitting element is formed and a color filter are manufactured by separate manufacturing processes, and they are bonded to each other to complete the light emitting device. Thus, the yield of the light emitting device is improved and the manufacture period is shortened.

Abstract: An electro-optical device having a plurality of pixels including a plurality of EL elements, wherein the electro-optical device provides a gray scale display by controlling a period of time at which the plurality of the EL elements emit light in one frame period; the plurality of the EL elements have a first electrode and a second electrode; the first electrode is held at a constant potential; and a potential of the second electrode changes in such a manner that a polarity of an EL driving voltage, which is a difference between the potentials applied to the first and second electrodes, is inverted for each one frame period.

Abstract: There is provided an electronic device in which the deterioration of the device is prevented and an aperture ratio is improved without using a black mask and without increasing the number of masks. In the electronic device, a first electrode (113) is disposed on another layer different from the layer on which a gate wiring (145) is disposed as a gate electrode, and a semiconductor layer of a pixel switching TFT is superimposed on the gate wiring (145) so as to be shielded from a light. Thus, the deterioration of the TFT is suppressed, and a high aperture ratio is realized.

Abstract: An electro-optical device having a plurality of pixels including a plurality of EL elements, wherein the electro-optical device provides a gray scale display by controlling a period of time at which the plurality of the EL elements emit light in one frame period; the plurality of the EL elements have a first electrode and a second electrode; the first electrode is held at a constant potential; and a potential of the second electrode changes in such a manner that a polarity of an EL driving voltage, which is a difference between the potentials applied to the first and second electrodes, is inverted for each one frame period.

Abstract: There is provided an electronic device having high reliability and high color reproducibility. A pixel structure is made such that a switching FET (201) and an electric current controlling FET (202) are formed on a single crystal semiconductor substrate (11), and an EL element (203) is electrically connected to the electric current controlling FET (202). The fluctuation in characteristics of the electric current controlling FET (202) is very low among pixels, and an image with high color reproducibility can be obtained. By taking hot carrier measures in the electric current controlling FET (202), the electronic device having high reliability can be obtained.

Abstract: A display device capable of displaying a picture of vivid colors maintaining a good balance of colors and a good balance of light-emitting brightnesses of the EL elements. The widths of the detour wirings supplying current to the power source feed lines are increased for those EL elements into which a current of a large density flows. This constitution decreases the wiring resistances of the detour wirings, decreases the potential drop through the detour wirings, and suppresses the amount of electric power consumed by the detour wirings.

Abstract: A display device capable of displaying a picture of vivid colors maintaining a good balance of colors and a good balance of light-emitting brightnesses of the EL elements. The widths of the detour wirings supplying current to the power source feed lines are increased for those EL elements into which a current of a large density flows. This constitution decreases the wiring resistances of the detour wirings, decreases the potential drop through the detour wirings, and suppresses the amount of electric power consumed by the detour wirings.

Abstract: There is provided an electronic device having high reliability and high color reproducibility. A pixel structure is made such that a switching FET (201) and an electric current controlling FET (202) are formed on a single crystal semiconductor substrate (11), and an EL element (203) is electrically connected to the electric current controlling FET (202). The fluctuation in characteristics of the electric current controlling FET (202) is very low among pixels, and an image with high color reproducibility can be obtained. By taking hot carrier measures in the electric current controlling FET (202), the electronic device having high reliability can be obtained.

Abstract: There is provided an electronic device in which the deterioration of the device is prevented and an aperture ratio is improved without using a black mask and without increasing the number of masks. In the electronic device, a first electrode (113) is disposed on another layer different from the layer on which a gate wiring (145) is disposed as a gate electrode, and a semiconductor layer of a pixel switching TFT is superimposed on the gate wiring (145) so as to be shielded from a light. Thus, the deterioration of the TFT is suppressed, and a high aperture ratio is realized.

Abstract: There is provided an electronic device having high reliability and high color reproducibility. A pixel structure is made such that a switching FET (201) and an electric current controlling FET (202) are formed on a single crystal semiconductor substrate (11), and an EL element (203) is electrically connected to the electric current controlling PET (202). The fluctuation in characteristics of the electric current controlling FET (202) is very low among pixels, and an image with high color reproducibility can be obtained. By taking hot carrier measures in the electric current controlling FET (202), the electronic device having high reliability can be obtained.

Abstract: There is provided an electronic device in which the deterioration of the device is prevented and an aperture ratio is improved without using a black mask and without increasing the number of masks. In the electronic device, a first electrode (113) is disposed on another layer different from the layer on which a gate wiring (145) is disposed as a gate electrode, and a semiconductor layer of a pixel switching TFT is superimposed on the gate wiring (145) so as to be shielded from a light. Thus, the deterioration of the TFT is suppressed, and a high aperture ratio is realized.

Abstract: The light emitting device according to the present invention is characterized in that a gate electrode comprising a plurality of conductive films is formed, and concentrations of impurity regions in an active layer are adjusted with making use of selectivity of the conductive films in etching and using them as masks. The present invention reduces the number of photolithography steps in relation to manufacturing the TFT for improving yield of the light emitting device and shortening manufacturing term thereof, by which a light emitting device and an electronic appliance are inexpensively provided.

Abstract: A current storing circuit capable of having a small area, a simple structure with the small number of devices, a low consumption current operation and high yield in manufacturing is provided. Applying the current storing circuit to the current-driving type of display device such as an OLED display device can improve the aperture rate of pixels and reliability of the display device as well as highly functionalize the display device. The invention is characterized by using a new semiconductor element in a shape of a transistor having plural drains or sources. When the semiconductor elements is used for both of a writing element and a driving element, reading in and storing a current value and outputting the current can be performed by only the two semiconductor elements, so that the area occupied by the devices would be easily reduced significantly.

Abstract: A display device capable of displaying a picture of vivid colors maintaining a good balance of colors and a good balance of light-emitting brightnesses of the EL elements. The widths of the detour wirings supplying current to the power source feed lines are increased for those EL elements into which a current of a large density flows. This constitution decreases the wiring resistances of the detour wirings, decreases the potential drop through the detour wirings, and suppresses the amount of electric power consumed by the detour wirings.

Abstract: A display device capable of displaying a picture of vivid colors maintaining a good balance of colors and a good balance of light-emitting brightnesses of the EL elements. The widths of the detour wirings supplying current to the power source feed lines are increased for those EL elements into which a current of a large density flows. This constitution decreases the wiring resistances of the detour wirings, decreases the potential drop through the detour wirings, and suppresses the amount of electric power consumed by the detour wirings.

Abstract: A current storing circuit capable of having a small area, a simple structure with the small number of devices, a low consumption current operation and high yield in manufacturing is provided. Applying the current storing circuit to the current-driving type of display device such as an OLED display device can improve the aperture rate of pixels and reliability of the display device as well as highly functionalize the display device. The invention is characterized by using a new semiconductor element in a shape of a transistor having plural drains or sources. When the semiconductor elements is used for both of a writing element and a driving element, reading in and storing a current value and outputting the current can be performed by only the two semiconductor elements, so that the area occupied by the devices would be easily reduced significantly.

Abstract: An inexpensive light emitting device and inexpensive electric equipment are provided. A substrate on which a semiconductor element or a light emitting element is formed and a color filter are manufactured by separate manufacturing processes, and they are bonded to each other to complete the light emitting device. Thus, the yield of the light emitting device is improved and the manufacture period is shortened.

Abstract: The light emitting device according to the present invention is characterized in that a gate electrode comprising a plurality of conductive films is formed, and concentrations of impurity regions in an active layer are adjusted with making use of selectivity of the conductive films in etching and using them as masks. The present invention reduces the number of photolithography steps in relation to manufacturing the TFT for improving yield of the light emitting device and shortening manufacturing term thereof, by which a light emitting device and an electronic appliance are inexpensively provided.

Abstract: An inexpensive light emitting device and inexpensive electric equipment are provided. A substrate on which a semiconductor element or a light emitting element is formed and a color filter are manufactured by separate manufacturing processes, and they are bonded to each other to complete the light emitting device. Thus, the yield of the light emitting device is improved and the manufacture period is shortened.